The most important way to prevent lung cancer is to avoid tobacco smoke. People who never smoke have the lowest risk of lung cancer. People who smoke can reduce their risk of lung cancer by stopping smoking, but their risk of lung cancer will still be higher than people who never smoked. Attempts to prevent lung cancer with vitamins or other treatments have not worked. For instance, beta-carotene, a drug related to vitamin A, has been tested for the prevention of lung cancer. It did not reduce the risk of cancer. In people who continued to smoke, beta-carotene actually increased the risk of lung cancer.
Recently, a large study called the National Lung Screening Trial showed that, in patients who are current or former heavy smokers, the use of a screening test called a low-dose helical (or spiral) computed tomography (CT or CAT) scan decreases the risk of death from lung cancer by 20%. A CT scan creates a three-dimensional picture of the inside of the body with an x-ray machine. A computer then combines these images into a detailed, cross-sectional view that shows any abnormalities or tumors.
CT scanning is not recommended for every smoker. Doctors still need to prove that screening everyone at risk for lung cancer reduces rates of death from lung cancer in the general population.